#include <bits//stdc++.h> #include <ext/pb_ds/assoc_container.hpp> #include <ext/pb_ds/tree_policy.hpp> using namespace std; using namespace __gnu_pbds; typedef tree<long long, null_type, less<long long>, rb_tree_tag, tree_order_statistics_node_update> ordered_set; typedef tree<long long, null_type, less_equal<long long>, rb_tree_tag, tree_order_statistics_node_update> ordered_multiset; #define ll long long #define iloop(m, h) for (auto i = m; i != h; i += (m < h ? 1 : -1)) #define jloop(m, h) for (auto j = m; j != h; j += (m < h ? 1 : -1)) #define kloop(m, h) for (auto k = m; k != h; k += (m < h ? 1 : -1)) #define pll pair<ll, ll> #define INF 1000000000000000 #define MOD1 1000000007 #define MOD2 998244353 #define MOD3 1000000009 ll n, m, t, cv[100005], t1, t2, a[100005]; vector<pll> adj[100005]; pll edge[100005]; bool vis[100005]; ll ma[100005]; vector<ll> rt; ll dfs(ll nd, ll pr) { vis[nd] = 1; ll fn = 0; for (auto it : adj[nd]) { if (it.first == pr) continue; if (vis[it.second]) { fn++; ma[it.first] = 2; cv[it.second]++; continue; } fn += dfs(it.second, it.first); a[nd] += a[it.second]; } fn -= cv[nd]; assert(fn >= 0); if (pr != -1) { if (fn != 0 || a[nd] == 0) ma[pr] = 2; else if (a[nd] > 0) ma[pr] = (nd == edge[pr].first ? 0 : 1); else ma[pr] = (nd == edge[pr].first ? 1 : 0); } return fn; } int main() { ios_base::sync_with_stdio(false); cin.tie(NULL); cin >> n >> m; iloop(0, m) { cin >> edge[i].first >> edge[i].second; edge[i].first--, edge[i].second--; adj[edge[i].first].push_back({i, edge[i].second}); adj[edge[i].second].push_back({i, edge[i].first}); } cin >> t; iloop(0, t) { cin >> t1 >> t2; t1--, t2--; a[t1]++, a[t2]--; } iloop(0, n) if (!vis[i]) dfs(i, -1); string c = "RLB"; iloop(0, m) cout << c[ma[i]]; }